CVE-2026-16401: Mozilla Firefox privilege escalation in Data Loss Prevention

Executive brief

A vulnerability in the Firefox web browser's Data Loss Prevention (DLP) component could allow for privilege escalation. This component is typically used in enterprise environments to prevent sensitive information from being leaked. An exploit could allow an attacker to bypass security restrictions or gain higher-level permissions within the browser environment.

Technical details

A privilege escalation vulnerability exists in the Data Loss Prevention (DLP) component of Mozilla Firefox. While specific technical details are restricted in the associated Bugzilla report (Bug 2052565), the flaw allows for an escalation of privileges within the browser's execution context. The vulnerability is rated as 'moderate' impact by Mozilla. It is reachable via web content and was resolved in Firefox version 153.

Affected products

• Mozilla Firefox < 153

Timeline

• 2026-07-21: advisory: Mozilla Foundation Security Advisory 2026-68 published.
• 2026-07-21: patched: Fixed in Firefox 153.

References

• https://bugzilla.mozilla.org/show_bug.cgi?id=2052565
• https://www.mozilla.org/security/advisories/mfsa2026-68/